Can Seaweed Make Better Solar Cells?

Extracts from marine plants can replace the expensive platinum in photovoltaic cells.

One of the infrequently-discussed ironies of renewable energy technologies is that they typically utilize many nonrenewable materials. In addition to silicon, photovoltaic cells commonly include metals like aluminum, silver, and platinum, as well as other materials such as glass and plastics. Although some of these nonrenewables are commonly occurring, others may be rare or expensive.

Dalian University of Technology professor Tingli Ma and a group of collaborators have developed a method of replacing the platinum used in solar photovoltaics with a renewable material: seaweed. In particular, Ma and her team have successfully utilized a biomass extract from brown algae as the electrode material in dye-sensitized solar cells (DSCs), in lieu of the commonly-used and more expensive platinum. Although preliminary experiments failed to demonstrate functional equivalency, in the most recent effort, the marine plant iteration exhibited similar electrocatalytic activity as the platinum version.

"Discovering novel chromophores and achieving record light-to-electricity conversion efficiencies makes the sourcing of photoactive and electroactive materials from seaweed an interesting finding, which, if chemically stable over reasonable timescales, could be used for commercial applications," remarked University of Bath chemist Aron Walsh in a Chemistry World story.

Blaine Brownell, AIA, is a regularly featured columnist whose stories appear on this website each week. His views and conclusions are not necessarily those of ARCHITECT magazine nor of the American Institute of Architects.